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831.
AIM: To evaluate the guiding effect of high-frequency stimulation (HFS) on renal denervation (RDN), and to compare the similarities and differences of blood pressure changes at the time of electrical stimulation and radiofrequency ablation. METHODS: A total of 6 Kunming dogs were included in this study. Renal artery abnormalities were excluded by angiography. High-frequency stimulation and radiofrequency ablation were performed at the same sites from distal to proximal segments of the renal artery. Invasive blood pressure (BP) was recorded during the whole procedure. The change of the blood pressure was analyzed. HE and Masson staining was adopted to detect the structural changes in the wall of the renal artery and surrounding tissues. The immumohistochemical staining for tyrosine hydroxylase (TH) was used to observe the renal nerve damage after ablation. RESULTS: Electrical stimulation and radiofrequency ablation were delivered in a total of 50 sites. The BP increasing response was induced at 34% sites (n=17), while the rest sites (66%, n=33) had no response. Compared with the baseline, HFS caused the increases in systolic BP of (0.34±3.38), (0.41±3.04), (10.47±5.73), (13.27±3.63), (10.17±1.87) and (0.78±1.87) mmHg in 6 serial 20 s time segments during 120 s of HFS at positive BP response sites. Similarly, the increases in systolic BP by (-0.88±3.44), (-1.64±3.47), (13.17±3.12), (12.82±3.21), (9.50±2.68) and (-6.09±2.21) mmHg were observed during 120 s of ablation procedure at the same sites in 6 serial 20 s time segments. At non-responding sites, HFS and ablation failed to cause a significant increase in systolic BP. The mean area of nerves in the response sites was (0.51±0.28) mm2, whereas that in non-response sites was (0.09±0.06) mm2 (P<0.01). The average absorbance values of TH in renal nerves at ablation and non-ablation sites were 0.031±0.015 and 0.085±0.018 (P<0.01), respectively. CONCLUSION: Renal sympathetic nerves can be effectively mapped by HFS. Radiofrequency ablation guided by HFS is valid to injure sympathetic nerves around renal artery. 相似文献
832.
Interaction of chlorhexidine with trisEDTA or miconazole in vitro against canine meticillin‐resistant and ‐susceptible Staphylococcus pseudintermedius isolates from two UK regions
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833.
834.
Ziegler PE Santucci F Lindergard G Nydam DV Wade SE Schaaf SL Chang YF Mohammed HO 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(2):148-159
This study investigated the utility of the polymerase chain reaction (PCR) protocol as a screening test for Cryptosporidium spp in 125 fecal samples from dairy cattle and wild rodents. Samples initially examined by fecal flotation and ELISA were evaluated using four PCR protocols (18S SSU rRNA, TRAP-C2, HSP70, and COWP), and the relative accuracy and agreement of PCR protocols was assessed. Although PCR can be both highly sensitive and accurate, the ability of these protocols to accurately detect DNA in samples can vary. A combination of techniques may be the best choice for to screen samples for this parasite. 相似文献
835.
信阳市南湾水库库区森林植被南湾水库库区的水资源涵养和水土保持具有重要的作用。本文对水库加区的森林植被的环境,资源状况,类型进行了调查分析,并提出了保护管理的建议。 相似文献
836.
837.
基因型对陆地棉花药离体培养反应的影响 总被引:3,自引:0,他引:3
对27种棉花基因型的花药在离体培养中的反应进行了比较,结果表明:所有的基因型在合适的培养条件下均能高频率地形成愈伤组织,但不同基因型间愈伤组织诱导率和诱导量不同;再生植株的花药比原始亲本的花药易诱导出愈伤组织;品种间杂种表现出部分优势,但不明显。本试验中,仅鲁棉6号和Siokra1-3两个品种诱导获得了胚性愈伤组织、胚状体和再生植株,且二者之间也存在着差别。从基因型在棉花花药培养中的效应、外界调控对棉花不同基因型花药培养效果的影响、棉花花药培养与体细胞培养基因型差异的比较等三个方面进行了讨论,提出了棉花花药培养愈伤组织诱导和植株再生是受两套遗传基因控制的遗传性状,并提出了棉花组织培养植株再生的阈值问题 相似文献
838.
The method to carry out time frequency analysis of engineering signal using wavelets transform is discussed and the formuli of quantitative relationship between the position & width of time frequency window of wavelet transform and the scale & sampling interval is put forward. 相似文献
839.
对影响脲醛树脂胶粘剂质量的主要因素如摩尔比、PH值、二次尿素加入点、反应温度、反应时间及原料质量等进行了分析,评价并提出最佳控制范围。 相似文献
840.
在黄土高原综合治理试区研究工作中,通过对枣子沟流域土地形成的自然环境条件和分异特点的分析,探讨了本区土地类型划分的原则、指标和分类体系,阐述了各种类型的形成条件、分异原因、属性特须、利用现状和土地类型的空间组合结构,并对本区土地资源进行了适宜性评价,提出今后合理利用的方向和途径。 相似文献